Drive for the stepped drums of calculating machines



Feb. l0, 1931. A. KoTrMANN 1,791,675

RIVE FOR THE STEPPED DRUMS OF CLCULTING yICHINES Original Fi'led Nov. 25, 1926 d fr lj y* l :ALE I.: I l @a i .c5/@M45 fm@ menue Feb. 1o, 1931 PATENT oFr-'lce AUGUST XOTTMANN, yor' sonnnnna, GERMANY, AssIGNon' 'roniIErNIscHE METALL- WAAREN UND MASCHINENFABRIK SMHE'RDA AKTIENGESELLSCHAFT, OF SOM- MERDA, GERMANY DRIVE FOR THE STEPPEI) DRUHS F CALCULATING MACHINES 'Original application led November 28, 1926, Serial No. 150,331, and in Germany December 10, 1925.

. Divided and this application led lay 13, 1927. Seria! No. 190,993.

This invention relates to calculating machines having stepped drums and refers more particularly to the driving mechanism of calculating machines as described and claimed in my patentl application Ser. No. A 150,331 filed Novelnber'23, 1926, of which the present application is a division. According to the construction shown in this application the stepped drums of the calculating machine are divided into groups and the groups of drums are rotated by the main drive in such a manner that'the left hand group always lags the adjacent right hand group for an angle of so many tooth pitches as tens transfer teeth are provided in the last mentioned group. To obtain this drive,

, shafts driving the separategroups must be provided. Intermediate shafts are in such a. case required between the main driving shaft and the shafts driving the groups and these intermediate shafts are rotated by the lnain shaft by means of toothed segments.

In the calculating machine according to the invention each group of stepped drums and each group of tens transfer cam-s consists of one unit (stepped drum, tenstransfer cam) so thatthe driving shafts for the groups may be omitted. The main drive shaft in this case extends, as in the usual bevel gear drive for l0 stepped drums, through the whole machine and directly drives, by means of bevel gear segments, the several groups (in the present case it can also be said the several single stepped drums as'each' group-consists of a single unit). These bevel gear segments are all of the same construction, but lfixed to the shaft in such`a manner that the one arranged to the left always lags the adjacent one to the right for an angle of one tooth pitch. These bevel gear segments engage with bevel gears whichA are directlyfkeyed to the shafts vof the'stepped drums. The bevel gears and bevel gear Segments lpave an equal `number of teeth, sothat the groups of stepped drums makejone revolution at 'each revolution of themain drive shaft.

, In the accompanying drawingsone molde of carrying out the inventionis shown dia- Q grammatically by way of examples v Fig. l is an elevation of the new drive for the stepped drums',

Fig. 2 is atop plan view ofthe drive shown in Fig. l,

Figs. 3-'8 arc detail views showing thc relative positions of the bevel gear segments,

and

Fig. 9- shows diagramlnatcally the tens transfer mechanism associated with the stepped drums.

In the construction shown in Figs. 1-8 the driving shaft 5 is journalled in bearings 2 and 3 at the front Wall l of the machine. The

A shaft 5 carries the bevel gear wheel segments the counting mechanism which are not driven bystep d drums may be driven in groups.

The definltions stepped drum and group of stepped drums therefore coincide. For-` this rea'son in the following description therev will be no longer any vreference made to groups Vof stepped drums and groups of tens transfer cams, but simply to step ed drums and tens transfer cams respective y."

The maindrive shaft 5 is arranged close to thel front ends ofthe stepped drum shafts 9, the bevel gear wheel segments of the man1 drive shaft 5 extend through the wall 1 and engage the bevel gear wheels 8. lThe bevel gear wheels 8 are fixed to theshafts 9 which` i carry also the stepped drums 10 and the sec' tors 11 provided with the tens teeth 12. 'In holes 13 in the front Wall' l are journalled square shafts`14 uponwhicli aren arranged the adjusting wheels 15 and the tens vsleeves rovided wit-hthe star discs 16 tensl transer cams or in the upper denominations of the counting mechanism the tens transfer cams 0x11 'ldlc stepped drums have a compass of 12 pitches, 9 pitches for the stepped teeth, one

simultaneously, the tens transfer cams of all denominations would act simultaneously. As this is not admissible, the arrangement is such that the stepped drum situated at the left hand side always lags for an angle of one pitch the adjacent drum to the right. This is obtained by staggered arrangement of the bevel gear Wheel segments 7 2 8 of the main drive shaft 5. As shown in Figs. 2, 4 and 5, the gear segments may be in phase and engage their 'associated gear wheels simultaneously, the lowermost drum having no transfer nlechanism.

For machines having n denominations the bevel gear wheel segments are parts of complete bevel gear wheels of a compassof 12+ (0r-l) pitches, 12 pitches for the teleth engaging the teeth of wheels 8 and (1L-1) pitches as play for the (1f-1) tens transfer. For the machine shown by way of eX- ample in Figs. 1-8 the segments therefore are parts of complete bevel gear wheelshaving a compass of 12+ (6 1) =l7 pitches (a play before and after engagement was already provided at the stepped drums and need therefore not to be provided again).

If now the shaft 5 is rotated from the zero position, the bevel gear wheel segments 71' and 72 come first into engagement with the bevel gear wheels 8 of the two lowermost denominations. If 4these Wheels have been turned through an angle corresponding to one pitch the bevel gear wheel segment 73 also comes into engagement and after rotation for a further pitch also the segment d'4 and so on. The stepped drumsituated at the left hand side together with the associated tens transfer cam therefore always lags the adjacent drum to the right for an angle of one pitch. The tens transfer teeth therefore come into engagement one after the other in the same succession. The tens'transfer is therefore actuated as required from the right to the left through the several denominations of the machine although the stepped drums have the small compass of only 12 pitches.

The advantage of thisfconstruction with regard to that pf the older application resides in the fact that the compass of the stepped drums has the smallest possible value and the drive is considerably simplified as all group driving shafts and intermediate shafts are dispensed with.

Calculating machines are already known in which the stepped drums are driven in such a manner that always the stepped drum arranged at the left hand side is started only when the adjancent drum to the right has been stopped. These machines have the disadvantage that the bevel gear wheel segments of themain drive shaft reach large dimensions, i. c. such large dimensions, that it is impossible to arrange the main drive shaft close in front of the ends of the stepped drums., In these machines, therefore, the main drive shaft/is arranged in YaY lower plane and connected to the stepped drums 9 by means of. intermediate bevel Ygear wheels. Also with regard to such machines the drive according to the invention is to be considered as a substantial simplification as considerably smaller segments are required and the intermediate bevel gear is dispensed with.-

What I claim is:

1. In a drive for the stepped. drums and tens transfer mechanisms of calculating machines, in combination, a-drive shaft, gear wheels associated with` said drums and tens transfer mechanisms, gear segments on said drive shaft. adapted to mesh with said gear wheels fon driving said' drums and transfer mechanisms, the segments associated with the two lowermost drums being in phase and the remaining segments and their associated chines, in combination, a drive shaft', gear wheels associated with said drums-and tens transfer mechanisms, gear segmentsI on said drive shaft adapted to mesh with said gear wheels for driving said drums and transfer mechanisms, the segments associated with the 'two lowermost drums being in phase and the remaining segments c,pand their associated drums being so arranged that the drum or transfer mechanism at the left hand side lags the adjacent drumor transfer mechanism to the right for an angular interval sufcient for the completion of the tens transfer from the preceding denomination.

3. In a drive for the stepped drums and tens transfer mechanisms of calculating machines, in combination, a drive shaft, gear wheels associated with said drums and tens transfer mechanisms, gear segments on said drive shaft adapted to mesh with said gear wheels for driving said drums and transfer mechanisms, the segments andv their associated drums being so arranged that the drum or transfer mechanism at the left hand side lags the adjacent drum or transfer mechamsm to the right for an angular interval sufficient for the completion of the tens transfer from the preceding denomination.

In testimony, whereof I have aiiixed my signature.

' AUGUST KOTTMANN. 

